The present inventive subject matter relates generally to medical instruments, and specifically to endoscopic devices and methods.
Endoscopes commonly contain a working channel, which may be used to introduce specially-designed diagnostic and therapeutic instruments into the area under view inside the body. In some systems, the working channel may be connected to a pump outside the body and used for suction or fluid delivery (irrigation) to the area of the distal tip of the endoscope. For example, a clear fluid, such as saline solution, may be injected through the working channel in order to clean the endoscope viewing window and/or clear debris from the area under view.
PCT International Publication WO 03/053226, whose disclosure is incorporated herein by reference, describes an endoscope for use in intravascular photographic imaging. In one embodiment, a fluid is injected via an open channel in order to dilute the blood in the vicinity of a target region to be imaged. A control unit controls the amount of injected fluid according to whether the imaging data meets a predetermined threshold of resolution or other measure of quality.
U.S. Patent Application Publication 2001/0004692, whose disclosure is incorporated herein by reference, describes an endoscopic spraying instrument, which can spray liquid uniformly over all directions. A rotatingly-guiding groove at the leading end of a liquid-supplying tube is rotated about an central axis within a liquid-rotating chamber at the leading end. The liquid is discharged forwardly from an ejection hole formed in the wall of the liquid-rotating chamber. An annular, protruded wall is spaced outwardly from the outer periphery of the ejection hole.